In a known method, a sample of a micro-organism colony is taken from an isolation box and seeded in a tube containing a liquid culture medium, the tube is then placed in an oven at 37.degree. C. for a period of at least three or four hours. An operator then looks to see how the colony has developed, and if it has developed sufficiently the operator dilutes the colony to obtain an inoculum of about 10 ml. The inoculum is then placed in a circularly symmetrical analyzer as described in French patent No. 2 280 895. This analyzer has a central receiving well which is closed by a stopper, and a plurality of analysis chambers disposed around the central well. These analysis chambers are connected to the central well via measuring antechambers. The analysis chambers initially contain reagents suitable for performing an antibiogram or an identification biogram. The operator puts the analyzer on a centrifuge in order to insert the inoculum simultaneously and in measured quantities into each of the analysis chambers. The analyzer is then placed in an oven at 37.degree. C. for a period of five to eight hours. Thereafter the analyzer is inserted into a photometer in order to read the results.
Preferred embodiments of the present invention considerably simplify the work to be performed by the operator by making the analysis method capable of being completely automated under conditions of optimum sterility.